Synonyms for Penetrating (same or very similar meaning)
WordNet sense 1 (having or demonstrating ability to recognize or draw fine distinctions):
acute, discriminating, incisive, keen, penetrative, piercing, knifelike
WordNet sense 2 (having the ability to perceive or understand; keen in discernment):
perceptive
WordNet sense 3 (having or made by a thin edge or sharp point; suitable for cutting or piercing):
sharp
From the ODE community, based on WordNet
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